Improvement in machines for threading bolts



' CHARLES SCHNEIDER lmprovementin Machines for Threading Bolts.

No. 120,903, Patented Nov .4,1 s71 CHARLES SCHNEIDER, OF NEWARK, NEW JERSEY.

IMPROVEMENT IN MACHINES FOR THREADING BOLTS.

Specification forming part of Letters Patent No. 120,903, dated November 14,1871.

To all whom it may concern:

Be it known that I, CHARLES SCHNEIDER, of Newark, in the county of Essex and State of New Jersey, have invented a new and Improved Movable Chuck for Screw-Guttin g Machines; and I do hereby declare the following to be a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawing forming part of this specification, in which- Figure 1 represents a back view of a machine provided with my improved movable chuck. Fig. 2 is a vertical transverse section of the same taken on the plane of the line 0 c, Fig. 1.

Similar letters of reference indicate corresponding parts.

This invention has for its object to construct a screw-cutting chuck which can be conveniently opened apart after a screw-thread has been cut, to enable the removal of the finished screw or bolt without necessitating the ordinary tedious process of unscrewing. The invention consists in making the chuck in sections, which are pivoted to sliding pins in such manner that they can be moved forward and swung apart conveniently after a screw has been cut; thereby considerable time in the cutting of bolts and screws is gained and the expense of their manufacture consequently reduced.

A in the drawing represents the stationary frame of a screw-cutting machine, of suitable size and form. B is the chuck, made in two sections, at and b. At the back both these sections are connected by and with pivot-pins d d, which have eyes on their outer ends and embrace stationary projecting pins 6 c. On these pins 0 the chuck-pivots d can slide. The sections a b are, for cutting a screw, secured together in an opening of the frame or plate A, so that the cuttingthreads or ribs will be in the proper position. Levers C O that are pivoted to the back of the plate A are carried into groovesff of the chucksections, to properly hold them in place. After the thread has been cut the levers O are swung off the chuck-sections and the latter slid forward, whereby they drop apart, as shown in Fig. 2, to release the bolt or screw. I prefer to make the chuck-sections tapering and the hole in A of cor responding form, to facilitate the desired opening of the sections. I

Having thus described my invention, I claim as new and desire to secure by Letters Patent The projecting pins 6 c and pivots d cl, having eyes at their outer ends, combined as described, and applied to the sections of screw-cuttin g dies, as and for the purpose specified.

CHARLES SCHNEIDER.

Witnesses:

Gno. W. MABEE, T. B. MOSHER. 

